I run Mac OS 10.6.8 and tried to download the trial version of ID from adobe.com, but it said it would only work with a newer OS. I googled and found a download of (an earlier?) free trial that would work with my OS and downloaded it. I opened and tried to set up a book but I had trouble -- perhaps because this is new to me, so I quit and tried to restart. Upon restart it said my trial had expired. I won't rent/buy this until I can see how well it works for my needs, and apparently can't download it from Adobe with my present OS. I sure won't upgrade my OS for a hundred reasons already discussed passionately online, but certainly not to just audition an app. Does anyone know why this trial ended in less than a day, or how to get it running again?

Frankly, I think you're wasting your time with that hardware. The only versions of ID that are still available through Adobe are a CS6 perpetual license, which supposedly will run on that system, but is lacking in features for epub if you are interested in that sort of thing, and will never seen any updates, or Creative Cloud by subscription, which will not run on your OS.